Merge pull request #225 from pperepelkin/to-one-rels-fix

Fix to one relationship entity table join for entity type

Author: DanielBroad

Incremental Store/EncryptedStore.m

@@ -414,6 +414,7 @@ - (NSIncrementalStoreNode *)newValuesForObjectWithID:(NSManagedObjectID *)object
 
     // enumerate properties
     NSDictionary *properties = [entity propertiesByName];
+    __block NSUInteger tableAliasIndex = 0;
     [properties enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSPropertyDescription *obj, BOOL *stop) {
         if ([obj isKindOfClass:[NSAttributeDescription class]]) {
             [columns addObject:[NSString stringWithFormat:@"%@.%@", table, key]];
@@ -434,18 +435,15 @@ - (NSIncrementalStoreNode *)newValuesForObjectWithID:(NSManagedObjectID *)object
                 if ([self entityNeedsEntityTypeColumn:destinationEntity]) {
                     // Get the destination table for the type look up
                     NSString *destinationTable = [self tableNameForEntity:destinationEntity];
-                    NSString *destinationAlias = [NSString stringWithFormat:@"T%lul",(unsigned long)destinationEntity.hash];
+                    NSString *destinationAlias = [NSString stringWithFormat:@"t%lu", (unsigned long)tableAliasIndex];
+                    tableAliasIndex++;
 
                     // Add teh type column to the query
                     NSString *typeColumn = [NSString stringWithFormat:@"%@.__entityType", destinationAlias];
                     [columns addObject:typeColumn];
 
-                    NSString *join = [NSString stringWithFormat:@" INNER JOIN %@ as %@ ON %@.__objectid=%@.%@", destinationTable, destinationAlias, destinationAlias, table, column];
-
-                    // this part handles optional relationship
-                    if (relationship.optional) {
-                        join = [join stringByAppendingFormat:@" OR %@.%@ IS NULL", table, column];
-                    }
+                    // Use LEFT JOIN as a relationship can be optional
+                    NSString *join = [NSString stringWithFormat:@" LEFT JOIN %@ as %@ ON %@.__objectid=%@.%@", destinationTable, destinationAlias, destinationAlias, table, column];
 
                     [typeJoins addObject:join];
 

exampleProjects/IncrementalStore/ClassModel.xcdatamodeld/ClassModel.xcdatamodel/contents

@@ -13,6 +13,7 @@
         <relationship name="manyToManyInverse" optional="YES" toMany="YES" deletionRule="Cascade" destinationEntity="Root" inverseName="manyToMany" inverseEntity="Root" syncable="YES"/>
         <relationship name="oneToManyInverse" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="Root" inverseName="oneToMany" inverseEntity="Root" syncable="YES"/>
         <relationship name="oneToOneInverse" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="Root" inverseName="oneToOne" inverseEntity="Root" syncable="YES"/>
+        <relationship name="oneToOneNilInverse" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="Root" inverseName="oneToOneNil" inverseEntity="Root" syncable="YES"/>
     </entity>
     <entity name="Root" representedClassName="ISDRoot" syncable="YES">
         <attribute name="name" optional="YES" attributeType="String" syncable="YES"/>
@@ -21,13 +22,14 @@
         <relationship name="multipleOneToManyChildB" optional="YES" toMany="YES" deletionRule="Nullify" destinationEntity="ChildB" inverseName="multipleOneToMany" inverseEntity="ChildB" syncable="YES"/>
         <relationship name="oneToMany" optional="YES" toMany="YES" deletionRule="Cascade" destinationEntity="Parent" inverseName="oneToManyInverse" inverseEntity="Parent" syncable="YES"/>
         <relationship name="oneToOne" optional="YES" maxCount="1" deletionRule="Cascade" destinationEntity="Parent" inverseName="oneToOneInverse" inverseEntity="Parent" syncable="YES"/>
+        <relationship name="oneToOneNil" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="Parent" inverseName="oneToOneNilInverse" inverseEntity="Parent" syncable="YES"/>
         <relationship name="recursiveManyToMany" optional="YES" toMany="YES" deletionRule="Nullify" destinationEntity="Root" inverseName="recursiveManyToManyInverse" inverseEntity="Root" syncable="YES"/>
         <relationship name="recursiveManyToManyInverse" optional="YES" toMany="YES" deletionRule="Nullify" destinationEntity="Root" inverseName="recursiveManyToMany" inverseEntity="Root" syncable="YES"/>
     </entity>
     <elements>
         <element name="ChildA" positionX="-119" positionY="144" width="128" height="75"/>
         <element name="ChildB" positionX="79" positionY="144" width="128" height="75"/>
-        <element name="Parent" positionX="-20" positionY="8" width="128" height="103"/>
-        <element name="Root" positionX="-236" positionY="8" width="128" height="165"/>
+        <element name="Parent" positionX="-20" positionY="8" width="128" height="120"/>
+        <element name="Root" positionX="-236" positionY="8" width="128" height="180"/>
     </elements>
 </model>

exampleProjects/IncrementalStore/ClassModels/ISDParent.h

@@ -16,6 +16,7 @@
 @property (nonatomic, retain) NSString * name;
 @property (nonatomic, retain) ISDRoot *oneToManyInverse;
 @property (nonatomic, retain) ISDRoot *oneToOneInverse;
+@property (nonatomic, retain) ISDRoot *oneToOneNilInverse;
 @property (nonatomic, retain) NSSet *manyToManyInverse;
 @end
 

exampleProjects/IncrementalStore/ClassModels/ISDParent.m

@@ -15,6 +15,7 @@ @implementation ISDParent
 @dynamic name;
 @dynamic oneToManyInverse;
 @dynamic oneToOneInverse;
+@dynamic oneToOneNilInverse;
 @dynamic manyToManyInverse;
 
 @end

exampleProjects/IncrementalStore/ClassModels/ISDRoot.h

@@ -16,6 +16,7 @@
 @property (nonatomic, retain) NSString * name;
 @property (nonatomic, retain) NSSet *oneToMany;
 @property (nonatomic, retain) ISDParent *oneToOne;
+@property (nonatomic, retain) ISDParent *oneToOneNil;
 @property (nonatomic, retain) NSSet *manyToMany;
 @property (nonatomic, retain) NSSet *multipleOneToManyChildA;
 @property (nonatomic, retain) NSSet *multipleOneToManyChildB;

exampleProjects/IncrementalStore/ClassModels/ISDRoot.m

@@ -15,6 +15,7 @@ @implementation ISDRoot
 @dynamic name;
 @dynamic oneToMany;
 @dynamic oneToOne;
+@dynamic oneToOneNil;
 @dynamic manyToMany;
 @dynamic multipleOneToManyChildA;
 @dynamic multipleOneToManyChildB;

exampleProjects/IncrementalStore/Tests/RelationTests.m

@@ -309,6 +309,20 @@ -(void)testFetchingOneToOneFromDatabase
     [self checkOneToOneWithChildA:YES childB:NO];
 }
 
+-(void)testFetchingOneToOneNilFromCache
+{
+    [self checkOneToOneNil];
+}
+
+-(void)testFetchingOneToOneNilFromDatabase
+{
+    // Make sure we're loading directly from DB
+    [self resetCoordinator];
+    [self createCoordinator];
+    
+    [self checkOneToOneNil];
+}
+
 -(void)testFetchingManyToManyFromCache
 {
     [self checkManyToManyWithChildACount:2 childBCount:3];
@@ -381,6 +395,12 @@ -(void)checkOneToOneWithChildA:(BOOL)childA childB:(BOOL)childB
         XCTAssertFalse([child isKindOfClass:[ISDChildA class]], @"One-to-one child is of wrong class, got: %@, expecting: %@", NSStringFromClass([child class]), NSStringFromClass([ISDChildB class]));
     }
 }
+  
+-(void)checkOneToOneNil
+{
+    ISDRoot *fetchedRoot = [self fetchRootObject];
+    XCTAssert(fetchedRoot.oneToOneNil == nil, @"We didn't set it, should be nil");
+}
 
 /// Checks that the root object has the correct number of many-to-many relational ChildA and ChildB objects
 -(void)checkManyToManyWithChildACount:(NSUInteger)childACount childBCount:(NSUInteger)childBCount